#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>

int main(int argc, char **argv)
{
	int fd;
	struct stat st;

	fd = open(argv[1], O_WRONLY | O_APPEND);
	if (fd == -1) {
		perror("open failed");
		return 0;
	}
	if (fstat(fd, &st)) {
		perror("stat failed");
		return 0;
	}
	printf("old file size %d\n", st.st_size);
	if (write(fd, "hello", 5) != 5) {
		perror("write failed");
		return 0;
	}

        if (fstat(fd, &st)) {
                perror("stat failed");
                return 0;
        }
        printf("new file size %d\n", st.st_size);
	if (fsync(fd)) {
		perror("fsync failed");
		return 0;
	}

	printf("rebooting"); fflush(stdout);
	system("reboot -f -n");
	return 0;
}